Possible cause

WARNING: This page is about a different car, the 2016 Mazda CX-5. However, it is still accessible from the selected car via links, so may be relevant.

Connector terminal disconnection, poor contact, damage, deformation, corrosion
Forward sensing camera (FSC) power supply voltage or body ground malfunction
Open circuit in wiring harness between connector C-42 and connector C-27
Open circuit in wiring harness between forward sensing camera (FSC) and connector C-27
Connector C-42 malfunction
Connector C-27 malfunction
Forward sensing camera (FSC) malfunction